In a world where the weeks seem to fly by, I’m pretty envious of anyone who can write a weekly blog and always manage to make it interesting and informative. Chris at Fernglade Farm is one of those people. Chris lives in Victoria about 100 km northwest of me and importantly, lives off-grid.

“For about a month either side of the winter solstice, my mind reflects upon the deficiencies of the off grid solar power system here. Don’t get me wrong, I love solar energy as it is a great source of electricity. It just happens to be subject to some deficiencies which generally show up at this time of year.”

Last week’s blog saw Chris adding another five solar panels to his system, making thirty in all. He made some important points about off-grid solar and solar in general.

If they get too low, they don’t always effectively power the things they’re meant to power (I assume that means not enough oomph).

The further you have to run electric cables from solar panels to the house (assuming they’re situated somewhere other than on the roof of the house they’re powering), the thicker/heavier the cable has to be to overcome heat losses.

Therefore, filling up the desert (aka Central Australia) with solar panels is going to be a difficult and expensive task, because the power has to be transported long distances to where it’s needed (and the high temperatures usually found in deserts reduce the output of the panels).

Location is ultra-important; the panels have to face the sun for optimum performance. That means north in our part of the world.

Cloudy winter weather can be a problem…..you need to get enough power to use, plus enough to keep the batteries optimally charged.

Chris aims to use about 7-8 kWh per day, that’s very low compared with about three times that for an average household.

So I considered my own usage. I’m still grid-connected, but would like to get off it. The battery cost is the main problem.

My electricity provider, United Energy, maintains a very useful internet site, called Energy Easy, where I can register and log in to see my power usage—hourly, daily, weekly, monthly and yearly. Below is a partial screen shot of the page. This sort of information has only become available since the changeover to smart meters.

The dark orange vertical bars above the line show how much power I took from the grid at the particular time. The lighter orange bars underneath the line show the excess power from the solar panels which went back to the grid. The difference between that and what the panels actually produced is what went from the panels straight into the house (that happens preferentially, before any excess is exported to the grid). That’s not shown on the graph. I can get that from the inverter readout and a bit of subtraction.

The line at the top, joining the little circles, is supposed to represent the average daily use for a household in my suburb. I get the actual figures by mousing over the relevant parts on the graph.

So on Monday June 5, I took 2.6 kWh from the grid and sent 2.4 kWh back to the grid (for which the retailer paid me the princely sum of 8 cents per kWh—and from July 1 it’s due to go down to 5 cents!). But the average use for other households was 16.9 kWh.

Working it all out, with my present lifestyle, I might be able to get away with an off-grid system that would need to provide at least 5-7 kWh of power per day and preferably a bit more. That’s a lifestyle with no air-conditioning in summer and no electric heating in winter (I have a wood fire) and no water heating (I have bottled gas). And my panels aren’t optimally placed—I don’t have a north-facing roof section; there are 8 panels facing east and 12 facing west.

So if people think that by going solar they can continue with their present energy-hungry lifestyles, then they may be in for a shock. Either they’ll need more solar panels than will fit on the average optimum-facing roof, a huge battery backup, or a combination of both.

The other important fact about solar systems is that they aren’t sustainable long-term. Solar panels are currently manufactured using the energy from fossil fuels; so are the batteries used to store the excess power. That’s not saying anything about the resources needed either, or whether we’re all going to be running electric cars as well as household appliances. If the batteries are going to be Li-ion type, is there enough lithium in the world to make all the batteries required? Where is it located? Are the countries where it’s located going to be willing to share it, or will they want to keep it for themselves? It has to be mined and processed—again using fossil fuels. To be truly sustainable, an energy source needs to provide enough energy and of a suitable type, to reproduce itself, plus enough additional energy to run the sort of society we want.

Solar energy is only a means of getting away from coal-fired electricity in the short term. It won’t be part of a long-term future. For the same reasons, neither will wind power.

Even in the short-term, assuming you had the money to install a solar-powered off-grid system, could you live off it? Probably yes….but not the way most of us want to live today.

I don’t think I could. Not one meal. But I think I could do two meals a day, particularly if they were low-carb.

If you look at the bottom of the second link article, you’ll see a panel showing four types of what’s called ‘intermittent fasting‘ :

alternate day fasting

the 5:2 diet

periodic fasting

time-restricted feeding.

About 18 months ago, I tried the 5:2 diet. I wasn’t exactly overweight, but I was carrying some extra poundage, indicated by the fact that only one pair of slacks still fitted me comfortably. Getting into the others was a bit of a struggle. It was either lose weight or buy some new clothes.

The 5:2 diet was hard. Cutting 2 days a week to 500 calories wasn’t easy. An egg is 100 calories! A small tin of flavoured tuna is 100 calories! 100 gm of steak is 250 calories! You’ve got to be joking! I would wake up in the night desperatelylonging for a piece of cheese! On the fasting nights I would go to bed thinking, “yippee, I can eat tomorrow!” I think I lasted a couple of weeks, then I changed it to cut food intake down to 1000 calories every day. That’s about the basal metabolic rate for someone my age and I figured that any extra exercise I did would be burning up those extra calories from my hips.

Over the course of 2-3 months I lost 8 kg. I felt much better; wasn’t so tired after a day’s work in the garden and lo and behold, all my slacks fitted again. Money saved on new clothes!

Of course, as with all diets, the weight came back again when I started eating normally. But only 4 kg of it. I deliberately kept biscuits, cakes and sweets off the menu from then on (well…..just a couple of pieces of chocolate with coffee after dinner—not half a block of the stuff).

Some time ago I discovered low-carb, or LCHF as it’s more commonly known (Google it…..there are hundreds of links) and I’ve switched to that. I don’t think of it as a Diet with a capital ‘D’, it’s more a lifestyle. I’ve given up rice and pasta; I’m eating far more vegetables, plus meat and fish, full fat dairy, stacks of butter and only minimal fruit (mainly what comes out of the garden). More weight is slowly coming off, too.

Anyway, that’s the reason I think I could ‘do’ two meals a day. According to the definition in the table I referred to above, I’m already on ‘time-restricted’ feeding without even trying. My last meal of the day is over and done with by 6 pm in the evening. I don’t eat again till around 8 am and I’m never really hungry then. I only eat because, well….it’s breakfast time and breakfast is what you do in the morning.

I would really like to get my blood pressure down naturally, without having to take the drugs I do and I’d really like to see if I can reverse (or lessen) the symptoms of the rheumatoid arthritis which hit me some 15 years ago. Worth a try.

And it might be a good rehearsal for when the wheels begin to fall off industrial agriculture and food availability becomes a bit tenuous.